1910 MERRILL CREEK PKY 2018-11-15

. Mr. Danen Peugh January 19, 2004 East Side Slope Conditions Analyzed Minimum Safety Factors Static Pseudostatic Existing conditions 2.48 1.66 After construction 238 1.64 Slope Across The Water Qualiry Pond Conditions A.nalyzed Minimum Safety Factors Static Pseudostatic Existing conditions 2.72 1.75 After construction 2.41 1.56 The results of our analyses demonstrate that loading conditions imposed on the slopes by development of the site as proposed will have no adverse impact on the slopes stability. Based on the results of our analyses, it is our opinion that the slopes are stable and that the project development as planned will not adversely impact or decrease the stability of the site slopes, provided surface drainage is controlled and prevented from flowing in an uncontrolled manner over the slope crest. We also recommend that the footings for the structure be set back a minimum horizontal distance of ten feet, measured from the edge of the footing to the slope face. Erosion The soils encountered on-site are classified as Everett Gravelly Loam by the Soil Conservation Service (SCS). With the existing slope gradients over the developed portion of the site, these soils will have a low potential for erosion when exposed. However, on the steep slopes, these soils will have a high potential for erosion if exposed. Erosion protection measures required by the City of Everett will need to be in place prior to starting grading activity on the site. DISCUSSION AND RECOMMENDATIONS General Based on our study, in our opinion, there are no geotechnical considerations that would preclude development as proposed. The building can be supported on conventional spread footings bearing on competent native soils or structural fill that is placed and compacted above these competent native soils. Floor slabs and pavements can be similarly supported. The native soils encountered at the site contain a sufficient amount of soil fines that will make them difficult to compact as structural fill when too wet. The ability to use native soil from site excavations as structural fill will depend on its moisture content and the prevailing weather conditions at the time of construction. If grading activities will take place during the winter season, the owner should be prepared to import free-d.raining granular material for use as structural fill and backfill. Detailed recommendations regarding these issues and other geotechnical design considerations are provided in the following sections. These recommendations should be incorporated into the final design drawings and construction specifications. Project No. T-5471 Page No. 4